IDV Jython Example

idv.py

setOffScreen(1)
idv.getStateManager().setViewSize(java.awt.Dimension(1000,1000)) #1000 x 1000 pixels


#Datasource (this can be made into a prompt for multiple model files)
dsStr = java.lang.String("/disk7/rkowch/IDV/mitfluids/netcdf/")
ModelFile = java.lang.String("IDVmitmodel2.nc")
dsStr = java.lang.String(dsStr.concat(ModelFile))
ds = makeDataSource(dsStr,"netcdf.grid")
print "Datasource Created"
print " "


#Get information about available time frames
AllTimes = ds.getAllDateTimes()  #<--A list of all times
AllTimesSize = AllTimes.size()   #<--Integer number of frames (first one is 0)
FirstTime = AllTimes.get(0)
LastTime = AllTimes.get(AllTimesSize - 1)
print "Number of Frames:  ",AllTimesSize
print "First Time Frame:  ",FirstTime
print " Last Time Frame:  ",LastTime
print " "


#Prompt user for time(s)
OneOrMoreTimesChoice = int(raw_input(
  "One time frame (0) or multiple time frames (1)?  "))
print " "
if OneOrMoreTimesChoice == 0:
  FrameOne = int(raw_input("Which time frame?  "))
elif OneOrMoreTimesChoice == 1:
  FrameOne = int(raw_input("Enter first frame:  "))
  FrameTwo = int(raw_input("Enter final frame:  "))
print " "


#Update times list
#Remove times before/after selected frame/interval
for i in range(0,FrameOne):
  RemovedTime = AllTimes.remove(0)

if OneOrMoreTimesChoice == 0: #No time interval
  FrameTwo = FrameOne         #in this case

for j in range((FrameTwo + 1),AllTimesSize):
  NewTimesSize = AllTimes.size()
  RemovedTime = AllTimes.remove(NewTimesSize - 1)
  SelectedTimes = AllTimes

SelectedTimesSize = SelectedTimes.size()
print "New Size of Times Array = ",SelectedTimesSize
FirstElement = AllTimes.get(0)
if SelectedTimesSize > 1:
  LastElement = SelectedTimes.get(SelectedTimesSize - 1)
  print "First Time selected ------> ",FirstElement
  print "Last Time selected -------> ",LastElement
elif SelectedTimesSize == 1:
  print "Time selected ------> ",FirstElement
print " "


#A DataChoice and DataSelection is created for each of the display
#controls. The DataSelection is set with the specified time frame/interval.
#The DataChoice selects each field that will be rendered. The available DataChoice
#objects are selected through each field's coded ID. However, the best way to
#select these IDs are through the Master List of DataChoices defined 'MasterListChs'.
#For this cylinder collapse model NetCDF file, notable IDs are below:
#  flowvectors = Flow Vectors (from U & V)
#  windspeed = Speed (from U & V)
#  relvort = Relative Vorticity (from U & V)
#  absvort = Absolute Vorticity (from U & V)
#  U = U
#  V = V
#  W = W
#  Temp = Potential Temperature


dsID = ds.getUniqueId()                   # A DataChoice object is created
ObjID = ds.getProperty(dsID)              # here, which is set before each
DataChce = ds.findDataChoice(ObjID)       # chosen field is rendered.


#Create a DataSelection object, and set it with the specified
#time frame/interval. 
DataSel = ds.getDataSelection()
DataSel.setTimes(SelectedTimes)


#Set the DataSelection with a specific area of the grid to be loaded
#into the bounding box (e.g. Northern Hemisphere on the GFS model).
#BoundBox format is: ( MaxLat , MinLon , MinLat , MaxLon ).
import ucar.unidata.data.GeoLocationInfo
GeoSel = DataSel.getGeoSelection(1)
BoundBox = ucar.unidata.data.GeoLocationInfo(1.0,0.0,0.0,1.0)
GeoSel.setBoundingBox(BoundBox)
DataSel.setGeoSelection(GeoSel)


#Create a list 'MasterListChs' that contains all available DataChoice objects.
#NOTE: This list is the best way to select a DataChoice, by using its
#      index in the list, rather than typing in its coded ID. The ID of any 
#      field can be found by opening the IDV interactively, loading the 
#      datasource, and placing the mouse pointer over the field. On the text
#      that is displayed, the first line is the ID of the desired field. But,
#      many fields, such as flowvectors, do not support the easy "type-in-ID"
#      method. It must be selected from the entire list of DataChoice objects.
MasterListChs = ds.getDataChoices()
#print MasterListChs #<=============Use this to print the "long-name" of each
                     #              field that is available for plotting.


#Prompt user for info on creating the 2D plot
Sptinfo = java.lang.String(raw_input("Enter 'field,c-type,vec(y/n),c-colortable,' "))
print " "

FrstChar = 0     #Ask for more info on vectors if: vec(y/n) = y
for i in range(2):
  comma = Sptinfo.indexOf(",",FrstChar)
  FrstChar = comma + 1
vecs = java.lang.String(Sptinfo.charAt(FrstChar))
if vecs.equals("y") == 1:
  Svcinfo = java.lang.String(raw_input("Enter vector parameters\
 'color,skip,width,size (~ 8.0)' "))
  print " "
else:
  Svcinfo = java.lang.String("null,0,0,0,")

Sctinfo = java.lang.String(raw_input("Enter contour\
 'interval,base,min,max,width,labels(y/n),' "))
print " "
Svwinfo = java.lang.String(raw_input("Enter 'azimuth,tilt,zoom-factor,' "))
print " "


#Put all inputs from user into lists
vwinfo = [0,0,0]
vcinfo = [0,0,0,0]
ptinfo = [0,0,0,0]
ctinfo = [0,0,0,0,0,0]
MTXgrp = [ctinfo,vwinfo,ptinfo,vcinfo]
STRgrp = [Sctinfo,Svwinfo,Sptinfo,Svcinfo]
for MTX,STR in zip(MTXgrp,STRgrp):
  l = len(MTX)
  FrstChar = 0
  for I in range(l):
    comma = STR.indexOf(",",FrstChar)
    Sval = str(STR.substring(FrstChar,comma))
    if  MTX == vwinfo             or \
       (MTX == ctinfo and I < 4)  or \
       (MTX == vcinfo and I == 3):
        Fval = float(Sval)
    if (MTX == vcinfo and I > 0)  or \
       (MTX == ctinfo and I == 4):
        Fval = int(Sval)
    if (MTX == vcinfo and I == 0) or \
        MTX == ptinfo             or \
       (MTX == ctinfo and I == 5):
        Fval = java.lang.String(Sval)
    MTX[I] = Fval
    FrstChar = comma + 1

vwinfo[0] = float(str(vwinfo[0])) #First element appears to be stored
				  #as a string, so this needs to be done.

#DISPLAY: POTENTIAL TEMPERATURE, 2D (COLOR or LINE) CONTOUR PLOT
#================================================================

#Plot Potential Temperature
if ptinfo[0].equals("theta") == 1:

#Set the field to be plotted now
  DataChce = MasterListChs.get(2)

#Check field that is currently plotting
  DataChceInfo = DataChce.getStringId()
  print "Current Field ------>",DataChceInfo


#Set the level by choosing it from the entire list of levels 'LevelList'
  LevelList = ds.getAllLevels(DataChce)
  LevelListSize = LevelList.size()
  FirstLevel = LevelList.get(0)
  LastLevel = LevelList.get(LevelListSize - 1)
#TRY TO FIND THE LEVEL UNIT AND PRINT IT BELOW IN PLACE OF 'm' ?
  print "Available Levels for","2D",DataChceInfo
  print "Level 0 =",FirstLevel,"m | Level",(LevelListSize - 1),"=",LastLevel,"m"
  LevelChoice = int(raw_input("Please enter desired Level index  "))

  SelectedLevel = LevelList.get(LevelChoice)
  print "Selected Level ------>",SelectedLevel,"m"
  print " "
  LevelasString = SelectedLevel.toString()
  LevelasDouble = java.lang.Double(LevelasString)
  import visad
  Level = visad.Real(LevelasDouble)  # Select the level for this 2D plot
  DataChce.setLevelSelection(Level)  # Set the level on this 2D plot


#Obtain only the data for the selected time(s)/level,
#create the display, and wait for it to render
  if ptinfo[1].equals("color") == 1:
    disptype = java.lang.String("planviewcontourfilled")
  elif ptinfo[1].equals("line") == 1:
    disptype = java.lang.String("planviewcontour")

  ThetaDATA = DataChce.getData(DataSel)
  dc = createDisplay(disptype,ThetaDATA)
  pause()



  if ptinfo[1].equals("color") == 1:
#Set up the color table
    ThetaColor = idv.getDisplayConventions().getParamColorTable("Temp")
    degC = dc.getRawDataUnit()  #<--Unit of data (celsius)
    ThetaColorRange = idv.getDisplayConventions().getParamRange("Temp",degC)
    ThetaColorRange.setMin(ctinfo[2])
    ThetaColorRange.setMax(ctinfo[3])
    ThetaColor.setRange(ThetaColorRange)
    ThetaColor.setTransparency(1.0)  #Adjust color transparency

#Apply the color table AND range to the display control
    dc.setColorTable(ThetaColor)
    dc.setRange(ThetaColorRange)

#Apply some other settings (color bar, display unit, etc.)
    dc.setColorScaleVisible(1)
    dc.setSettingsDisplayUnit(degC)

#Set the contouring properties (for BOTH color & line options)
  contours = idv.getDisplayConventions().findDefaultContourInfo("Temp")
  if ptinfo[1].equals("line") == 1:
    import ucar.unidata.util.ColorTable
    linecolor = ucar.unidata.util.ColorTable()
    usercolor = idv.getDisplayConventions().getColor(ptinfo[3])
    usercltb = java.util.ArrayList(1)
    usercltb.add(0,usercolor)
    linecolor.setTable(usercltb)
    dc.setColorTable(linecolor)
  contours.setInterval(ctinfo[0])
  contours.setBase(ctinfo[1])
  contours.setMin(ctinfo[2])
  contours.setMax(ctinfo[3])
  contours.setLineWidth(ctinfo[4])
  contours.setIsLabeled(ctinfo[5].equals("y"))  #<--Contour labels (Yes/No)
  dc.setContourInfo(contours)


#Set the Title of the Display on the Main Screen, and apply all of our
#preferences for this Display Control.
  if ptinfo[1].equals("color") == 1:
    ThetaDispTemp = java.lang.String("Color Contoured Potential Temperature at Level ") 
  elif ptinfo[1].equals("line") == 1:
    ThetaDispTemp = java.lang.String("Line Contoured Potential Temperature at Level ")

  ThetaDispTemp = java.lang.String(ThetaDispTemp.concat(LevelasString))
  ThetaDispTemp = java.lang.String(ThetaDispTemp.concat(" m"))
  dc.setDisplayListTemplate(ThetaDispTemp)
  if ptinfo[1].equals("line") == 1:
    dc.setDisplayListColor(usercolor)
  else:
    ColorYellow = idv.getDisplayConventions().getColor('yellow')
    dc.setDisplayListColor(ColorYellow)   #<--Title is Yellow for filled contours
  dc.applyPreferences()


#DISPLAY: VECTOR PLAN VIEW (FROM U AND V FIELDS), only for COLOR-FILLED Theta
#============================================================================

if ptinfo[2].equals("y") == 1:
#Set the field to be plotted now. This MUST be selected from the
#list of DataChoices. NOTE: Only one DataChoice may be selected at any
#time. Therefore, the object 'DataChce' is simply changed as new fields
#are selected for rendering.
  DataChce = MasterListChs.get(8)


#Print current field that is plotting
  DataChceInfo = DataChce.getStringId()
  print "Current Field ------>",DataChceInfo


#IMPORTANT: The display control for the Vector Plan View requires data
#from all levels in the file. Thus, the level selection must include
#all possible levels when loading. The actual level for the display is set with 
#another function. But this might be required just for this NetCDF file only.
  FromFirstLevel = DataSel.getFromLevel()
  ToLastLevel = DataSel.getToLevel()
  DataSel.setLevelRange(FromFirstLevel,ToLastLevel)
  DataSel.setTimes(SelectedTimes) #<--should be reset whenever DataChce changes

#Obtain only the data for the selected time(s)/level,
#create the display, and wait for it to render
  WindVectorDATA = DataChce.getData(DataSel)
  dc = createDisplay('planviewflow',WindVectorDATA)
  pause()


#LevelChoice is already selected with the Potential Temperature control above
  SelectedLevel = LevelList.get(LevelChoice)


#Set these properties on the vectors: Display Range, Color, Level,
#                                     Size, Skip Factor in XY, and Line Width.
#NOTE: For flow vectors, setting the color is different. This
#display control doesn't use color tables. So the color is set
#through a 'color' object in the method setColor(). Some other features
#in dcTwo are also not available (e.g. Color Bar).
  VectorValueRange = dc.getColorRangeFromData()               # Display Range
  dc.setFlowRange(VectorValueRange)
  VectColor = idv.getDisplayConventions().getColor(vcinfo[0]) # Color
  dc.setColor(VectColor)
  dc.setSettingsLevel(SelectedLevel)                          # Level
  dc.setFlowScale(vcinfo[3])                                  # Vector Size
  dc.setSkipValue(vcinfo[1])                                  # Skip Factor
  dc.setLineWidth(vcinfo[2])                                  # Line Width


#Set the Title of the Display on the Main Screen, and apply all of our
#preferences for this Display Control.
  LevelasString = SelectedLevel.toString() #<--We need the level value in a String
  FlowDispTemp = java.lang.String("Flow Vectors at Level ")
  FlowDispTemp = java.lang.String(FlowDispTemp.concat(LevelasString))
  FlowDispTemp = java.lang.String(FlowDispTemp.concat(" m"))
  dc.setDisplayListTemplate(FlowDispTemp)
  dc.setDisplayListColor(VectColor) #Title's color is the vector color
  dc.applyPreferences()


#OVERALL VIEW OF THE FINAL IMAGE
#=================================================================

#Get a ViewManager with a Navigation Display
VM = idv.getViewManager()
NavDis = VM.getNavigatedDisplay()


#Set vertical scale (important for isosurfaces, or when layering 2D plots),
#turn the bounding box on, and set the desired viewing angle.
NavDis.setVerticalRange(-0.1,0) #(Bottom, Top) in meters
NavDis.setBoxVisible(1)
NavDis.rotateView(vwinfo[0],vwinfo[1])        #(Azimuth, Tilt) in degrees


#Get the DisplayMaster to zoom in/out of the overall view by changing
#the scaling factor (1.0 by default). Addition of this parameter to
#the web interface should be useful too. NOTE: For some reason,
#VM.getAspectRatio() returns NULL, which is very strange for a display!
DM = VM.getMaster()
DM.zoom(vwinfo[2])
VM.setMasterActive()


#Write output file
if OneOrMoreTimesChoice == 0:
  writeImage("hzt.png")
elif OneOrMoreTimesChoice == 1:
  writeMovie("hzt.gif")

#END